Automobile heater



Jan. 23, 1940. H. DE N. MccoLLuM 2,188,152

AUTOMOBILE HEATER Filed Jan. 6, 1938 2 Sheets-Sheet 1 Jan, 23, 1940. H. J. DEN. MccQLLuM AUTOMOBILE HEATER Filed Jan. 6, 1958 2 Sheets-Sheet 2 gif/31S Patented Jan. 23, 1940 UNITED STATES PATENT OFFICE I AUTOMOBILE HEATER Henry J. De N. McCollum, Evanston, Ill.

Application January 6, 1938, Serial No. 183,598

9` Claims.

My invention relates generally to automobile heaters, and more particularly to heaters of the internal combustion type. The present invention is an improvement on the heater shown in my 5 prior applications, Seri/a1 No. 61,213, filed January 28, 1936, and Serial Nos. 120,523 and 120,524, filed January 14, 1937.

In using an automobile heater of the internal combustion type upon an automobile, the gases l of combustion from the heater are drawn into the intake manifold of the automobile engine. Compensation for this additional supply of gases to the intake manifold may easily be made by' regulating` the engine carburetor. so as slightly to in' l crease the idling speed of the engine. Of course this difficulty is encountered relatively infrequently, and only when the carburetor is very delicately adjusted to the needs of the engine.

In accordance with my invention, I provide.

means, controlled by the heater, for securing more uniform idling and normal operation of the engine irrespective of whether or not the heater is in operation. Such means may assume many different forms, but a` few of the many ways in which the invention may be embodied being dis- It is a further object of my invention to provide automatic means for admitting a restricted amount of air to the intake manifold of the engine during the periods in which the heater is in operation.

Other objects will appear from the following description, reference being had to the accompanying drawings, in which:

4" Fig. 1 is a central longitudinal sectional view of a heater shown installed upon an automobile and including a thermostatically operated valve for admitting air to the intake manifold of the engine.

45 Fig. 2 is a transverse sectional view taken on the line 2-2 of Fig. 1;

Fig. 3 is a fragmentary longitudinal sectional view of a heater incorporating a modified form of the invention.

5u The heater comprises generally a combustion chamber Ill formed in a casting I2 which is secured to a back plate I4. The latter is connected by brackets I6 to the dash I8 ofthe Vehicle. A radiator 20 is secured to the combustion chamber casting I2 and is surrounded by a shell 22 over which heat radiating ns 24 are secured. Within the radiator 20 is a circultous passageway which terminates adjacent a nozzle 24 which forms means for compensating for changes in the degree of vacuum in the intake manifold. This ,5 nozzle communicates with a passageway 26 in the casting I2 to which Ia fitting 28 is connected, the latter being connected by a conduit 30 with the intake manifold 32 4of the engine. A valve 34 is engageable with the mouth of the nozzle 24 and 10 is operable by means of a control button 36. Liquid fuel is supplied to the heater from a reservoir 38, which may be either the oat bowl of the engine carburetor or a separate auxiliary reservoir for liquid fuel. The fuel is drawn from 15 the reservoir 38 through a conduit 40 to a carbureting device 42 where the fuel is mixed with the proper amount of air to form a combustible mixture which is fed through a pipe 44 and a tube .46 to the combustion chamber. 20

At the side of the combustion chamber I0 is 1ocated an igniter chamber which communicates with the combustion chamber through a large port 48. The igniter is preferably a coil of high resistance wire which may be electrically heated 25 to incandescence and thereby ignite the mixture of liquid fuel and air passing through the combustion chamber. The combustion chamber is partially closed by a slightly porous refractory reigniter plug 52 which has passageways extend- 30 ing therethrough for the flow of the products o combustion.

The air from the passenger compartment of the vehicle is' circulated past the heat radiating ns 24 by means of ya fan 54 driven by a motor 56. 35 `A suitable switch mechanism 58 is mounted adjacent the end of the radiator 20 and is arranged to be controlled by the button 36 and by a strip of thermostatic bimetal 60 which is in heat conducting relationship with the radiator. This switch mechanism and its method of operation is more fully disclosed and claimed in my aforesaid application, Serial No. 120,524. It will suffice here to say that the switch is operable when the control button is pulled outwardly to open the valve 34, to close a circuit connecting the igniter with a source of current, and is operated thereafter by the thermostatic bimetal strip 60 to open the igniter circuit and to close a circuit connecting the fan motor 56 with the source of 50 current. When the control button 36 is pushed inwardly, the valve 34 is closed and the circuits supplying both the fan motor and the igniter are opened.

As thus far described, the heater is disclosed in my aforesaid applications. The improvement of the present invention relates particularly to the. provision of means for admitting additional air to the intake manifold of the engine whenever the heater is in operation. This means com.-

prises the fittin-g 28 which is interposed between the discharge passageway 26 and the conduit 30. This tting is provided with an opening 62 which, when the heater is cold, is closed by a thermostatically operated valve 64. In the drawings, vthe valve 36 is illustrated as comprising merely a strip of bimetal secured in position so that its end ymaycover the opening 62 whenever the heater has not been in operation for some time and has thus cooled om When, however, the heater has been in operation for a short time, the hot gases of combustion passing through the fitting 28 will transmit heat to the fitting and to the valve 64, causing the latter to swing outwardly and uncover the port 62. In this way, whenever the heater is operating, a certain predetermined quantity of air willbe admitted to the passageway in the fitting 28 and thereby serve to dilute the 'gases which are supplied through this passageway and through the conduit 30' to the intake manifold of the engine.`

This dilutant air mixes with the exhaust gases from-the heater, and together the gases flow into the intake manifold. When the heater is not in l operation and the fitting. 28 has thus cooled to a relatively low temperature, the thermostatic bimet'al valve 64 will again flex toward its seat at the end of the port 62, and shut off the supply of diluting air.

The same object may be obtained by means of'a manually operated vent valve such as shown in Fig. 3, wherein the control rod 66 to which the control knob or handle 36 isA secured is provided With an extension stem '68 which projects through the passageway 26 and has its inner end guided in a passageway 'I2 formed in an el-l bow tting 69. The end 10 of the stem 62 normally obstructs a passageway 'i4 formed in the elbow fitting' 69, but is adapted to uncover this.

passageway when the control button 36 is pulled `outwardly to cause operation of the heater, and thus admit additional air from the atmospherey i to the intake manifold during the period that the heater is in operation.

In operation, each of the modifications will operate in substantially the same manner, i. e., to admit a predetermined proportion of air from the atmosphere to the intake manifold whenever the heater is in operation, and thereby improve the performance of the engineby assuring a more uniform supply of mixture of fuel and air thereto. The embodiment of Figs. 1 and 2 operates to admit auxiliary air to the intake manifold very shortly after the heater has commenced operation as determined by the temperature ofl the gases flowing through the fitting 28, while in the construction of Fig. 3, the auxiliary supply of air is manually controlled as an incident to the manual control of the operation of the heater.

While I have shown and described preferred embodiments of my invention, it will be vreadily understood by those skilled in the art that varia' tions may be made in the construction disclosed without departing from the basic features of my invention. I therefore do not wish to be limited to the precise construction disclosed, but wish to include within the scope of my invention all such modifications and variations which will readilysuggest themselves. l

What I claim as new and desire to secure by United States Letters Patent is: 1. In an automobile heater of the internal combustion type in which the products of combustion are conveyed to the intake manifold of the automobile engine, the combination of an apertured conduit connecting the heater with the intake manifoldl of the engine, and a bimetallic thermostatic element secured to said conduit adjacent said aperture and normally closing the latter, said thermostatic element being adapted when heated by the gases of combustion from said heater to move away from said aperture and permit the admission of atmospheric air to said conduit.

2. In an automobile heater of the internal combustion type in which the products of combustion are conveyed to the intake manifold of the automobile engine and the reduced pressure in said intake manifold is utilized to draw the fuel mixture into the heater and withdraw the products of combustion therefrom, the combination of a control device to control the starting and stopping of the operation of the heater, and a valve operable by said control device to admit atmospheric air to the products of combustion withdrawn from said heater when said control device is in heater operating position.

3. In an automobile heater of the internal combustion type, the combination of a combustion chamber, means to supply a combustible mixture of fuel and air to said chamber, means to ignite the mixture in .said chamber, a radiator receiving products of combustion from said 3 mixture of liquid fuel and air to said combustion chamber, means to ignite the mixture in said chamber, a radiator for receiving the products of combustion from said chamber, a conduit for conveying the products of combustion from said radiator to the intake manifold of the automobile engine, and means operable incidental to initiation of operation of the heater to admit atmospheric air at a restricted rate to said conduit.

5. In an automobile heater of the internal combustion type, the combination of a combustion chamber, means tosupply a combustible mixture of liquid fuel and air to said combustion chamber, means to ignite the mixture in said chamber, a radiator for receiving the products of combustion from said chamber, a conduit for conveying the products of combustion from said radiator to the intake manifold of the automomobile engine, a control knob on said heater for optionally rendering said heater operative or inoperative, an aperture in said discharge conduit, and a valve operable by said control knob to close said aperture when said control knob is in the position assumedwhen the heater is inoperative and adapted to uncover said aperture when said control knob is moved to the position assumed when the heater is in operation.

l 6. In an automobile heater of the internal combustion engine type', the combination of an "on" and "o control therefor, means for conveying the gases oi combustion from the heater to the intake manifold of the engine of the vehicle in which the heater is mounted, and thermostatically operable means associated with said conduit for admitting atmospheric air thereto whenever said conduit is heated to a predetermined temperature due to the passage of the gases of combustion therethrough.

7. In an automobile heater of the internal combustion type in which the products of combustion are conveyed to the intake manifold of the automobile engine, the combination of a conduit connecting the heater with the intake manifold ofthe engine, said conduit having an aperture therein, and a, temperature responsive valve cooperable with said aperture and closing the latter when the temperature ofY said conduit is relatively low, a said valve being adapted when said conduit is heated to a relatively high temperature to move away from said aperture, thereby to admit atmospheric air to said conduit.

8. In an automobile heater of the internal combustion type in which the products of combustion are conveyed to the intake manifold of the automobile engine, the combination of an apertured conduit connecting the heater with the intake manifold of the engine, and a, thermostatically operated valve positioned adjacent said aperture and normally closing the latter, said thermostatic valve being adapted when heated by the gases of combustion from said heater to move away from said aperture and permit the admission of atmospheric air to said conduit.

9. In an automobile heater of the internal combustion type, the combination of a combustion chamber, means to supply a combustible mixture of fuel and air to said chamber, means to ignite the mixture in said chamber, aconduit connected to said combustion chamber and leading to the intake manifold of the engine, means to admit a restricted amount of atmospheric air for n iixture with the products of combustion owing through said conduit, and means for controlling the operation of said air admitting means incidental to the control of the operation of the heater.

HENRY J. DE N. McCOLLUM. 

